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<FONT color="green">001</FONT>    package maze.model;<a name="line.1"></a>
<FONT color="green">002</FONT>    <a name="line.2"></a>
<FONT color="green">003</FONT>    import java.awt.Dimension;<a name="line.3"></a>
<FONT color="green">004</FONT>    import java.io.DataInputStream;<a name="line.4"></a>
<FONT color="green">005</FONT>    import java.io.DataOutputStream;<a name="line.5"></a>
<FONT color="green">006</FONT>    import java.io.File;<a name="line.6"></a>
<FONT color="green">007</FONT>    import java.io.FileInputStream;<a name="line.7"></a>
<FONT color="green">008</FONT>    import java.io.FileNotFoundException;<a name="line.8"></a>
<FONT color="green">009</FONT>    import java.io.FileOutputStream;<a name="line.9"></a>
<FONT color="green">010</FONT>    import java.io.IOException;<a name="line.10"></a>
<FONT color="green">011</FONT>    import java.io.InputStream;<a name="line.11"></a>
<FONT color="green">012</FONT>    import java.io.Serializable;<a name="line.12"></a>
<FONT color="green">013</FONT>    import java.util.ArrayList;<a name="line.13"></a>
<FONT color="green">014</FONT>    import java.util.Arrays;<a name="line.14"></a>
<FONT color="green">015</FONT>    import java.util.BitSet;<a name="line.15"></a>
<FONT color="green">016</FONT>    import java.util.List;<a name="line.16"></a>
<FONT color="green">017</FONT>    import java.util.Random;<a name="line.17"></a>
<FONT color="green">018</FONT>    import java.util.Set;<a name="line.18"></a>
<FONT color="green">019</FONT>    import java.util.TreeSet;<a name="line.19"></a>
<FONT color="green">020</FONT>    <a name="line.20"></a>
<FONT color="green">021</FONT>    import maze.util.ListenerSubject;<a name="line.21"></a>
<FONT color="green">022</FONT>    <a name="line.22"></a>
<FONT color="green">023</FONT>    /**<a name="line.23"></a>
<FONT color="green">024</FONT>     * Represents all the walls of a This class extends<a name="line.24"></a>
<FONT color="green">025</FONT>     * {@link maze.util.ListenerSubject} which allows it to notify listeners when a<a name="line.25"></a>
<FONT color="green">026</FONT>     * wall changes and provide the {@link maze.model.MazeCell} that contains the<a name="line.26"></a>
<FONT color="green">027</FONT>     * changed wall.<a name="line.27"></a>
<FONT color="green">028</FONT>     */<a name="line.28"></a>
<FONT color="green">029</FONT>    public final class MazeModel extends ListenerSubject&lt;MazeCell&gt; implements Cloneable, Serializable<a name="line.29"></a>
<FONT color="green">030</FONT>    {<a name="line.30"></a>
<FONT color="green">031</FONT>       /**<a name="line.31"></a>
<FONT color="green">032</FONT>        * A &lt;code&gt;MazeWall&lt;/code&gt; object represents the model for a single wall in a<a name="line.32"></a>
<FONT color="green">033</FONT>        * maze. It has a method to check whether the wall is set/enabled or not. And<a name="line.33"></a>
<FONT color="green">034</FONT>        * to change its status.<a name="line.34"></a>
<FONT color="green">035</FONT>        */<a name="line.35"></a>
<FONT color="green">036</FONT>       public static interface MazeWall<a name="line.36"></a>
<FONT color="green">037</FONT>       {<a name="line.37"></a>
<FONT color="green">038</FONT>          public boolean isSet();<a name="line.38"></a>
<FONT color="green">039</FONT>    <a name="line.39"></a>
<FONT color="green">040</FONT>          public void set(boolean value);<a name="line.40"></a>
<FONT color="green">041</FONT>       }<a name="line.41"></a>
<FONT color="green">042</FONT>    <a name="line.42"></a>
<FONT color="green">043</FONT>       /**<a name="line.43"></a>
<FONT color="green">044</FONT>        * A maze is generally 16 x 16<a name="line.44"></a>
<FONT color="green">045</FONT>        */<a name="line.45"></a>
<FONT color="green">046</FONT>       private static final int DEFAULT_SIZE = 16;<a name="line.46"></a>
<FONT color="green">047</FONT>    <a name="line.47"></a>
<FONT color="green">048</FONT>       public static final int EAST = 1;<a name="line.48"></a>
<FONT color="green">049</FONT>       public static final int NORTH = 0;<a name="line.49"></a>
<FONT color="green">050</FONT>       public static final int SOUTH = 2;<a name="line.50"></a>
<FONT color="green">051</FONT>       public static final int WEST = 3;<a name="line.51"></a>
<FONT color="green">052</FONT>       /**<a name="line.52"></a>
<FONT color="green">053</FONT>        * Column walls.<a name="line.53"></a>
<FONT color="green">054</FONT>        */<a name="line.54"></a>
<FONT color="green">055</FONT>       private BitSet cwalls;<a name="line.55"></a>
<FONT color="green">056</FONT>       /**<a name="line.56"></a>
<FONT color="green">057</FONT>        * Number of rows or height of this maze.<a name="line.57"></a>
<FONT color="green">058</FONT>        */<a name="line.58"></a>
<FONT color="green">059</FONT>       private int height;<a name="line.59"></a>
<FONT color="green">060</FONT>       /**<a name="line.60"></a>
<FONT color="green">061</FONT>        * Row walls.<a name="line.61"></a>
<FONT color="green">062</FONT>        */<a name="line.62"></a>
<FONT color="green">063</FONT>       private BitSet rwalls;<a name="line.63"></a>
<FONT color="green">064</FONT>       /**<a name="line.64"></a>
<FONT color="green">065</FONT>        * Number of columns or width of this maze.<a name="line.65"></a>
<FONT color="green">066</FONT>        */<a name="line.66"></a>
<FONT color="green">067</FONT>       private int width;<a name="line.67"></a>
<FONT color="green">068</FONT>    <a name="line.68"></a>
<FONT color="green">069</FONT>       /**<a name="line.69"></a>
<FONT color="green">070</FONT>        * Create a maze with the default size.<a name="line.70"></a>
<FONT color="green">071</FONT>        */<a name="line.71"></a>
<FONT color="green">072</FONT>       public MazeModel()<a name="line.72"></a>
<FONT color="green">073</FONT>       {<a name="line.73"></a>
<FONT color="green">074</FONT>          this(DEFAULT_SIZE, DEFAULT_SIZE);<a name="line.74"></a>
<FONT color="green">075</FONT>       }<a name="line.75"></a>
<FONT color="green">076</FONT>    <a name="line.76"></a>
<FONT color="green">077</FONT>       /**<a name="line.77"></a>
<FONT color="green">078</FONT>        * Construct a new maze model with the given dimensions.<a name="line.78"></a>
<FONT color="green">079</FONT>        * @param width The width or number of columns of the new maze.<a name="line.79"></a>
<FONT color="green">080</FONT>        * @param height The height or number of rows of the new maze.<a name="line.80"></a>
<FONT color="green">081</FONT>        */<a name="line.81"></a>
<FONT color="green">082</FONT>       public MazeModel(int width, int height)<a name="line.82"></a>
<FONT color="green">083</FONT>       {<a name="line.83"></a>
<FONT color="green">084</FONT>          this.width = width + width % 2;<a name="line.84"></a>
<FONT color="green">085</FONT>          this.height = height + height % 2;<a name="line.85"></a>
<FONT color="green">086</FONT>          rwalls = new BitSet(width * (height - 1));<a name="line.86"></a>
<FONT color="green">087</FONT>          cwalls = new BitSet( (width - 1) * height);<a name="line.87"></a>
<FONT color="green">088</FONT>          setWall(1, height, EAST);<a name="line.88"></a>
<FONT color="green">089</FONT>       }<a name="line.89"></a>
<FONT color="green">090</FONT>    <a name="line.90"></a>
<FONT color="green">091</FONT>       /**<a name="line.91"></a>
<FONT color="green">092</FONT>        * Clears the 4 walls around the center peg as is required by the rules for a<a name="line.92"></a>
<FONT color="green">093</FONT>        * legal maze. After calling this a call to {@link #isCenterLegal()} should<a name="line.93"></a>
<FONT color="green">094</FONT>        * return true.<a name="line.94"></a>
<FONT color="green">095</FONT>        */<a name="line.95"></a>
<FONT color="green">096</FONT>       public void clearCenterWalls()<a name="line.96"></a>
<FONT color="green">097</FONT>       {<a name="line.97"></a>
<FONT color="green">098</FONT>          final int centerY = height / 2;<a name="line.98"></a>
<FONT color="green">099</FONT>          final int centerX = width / 2;<a name="line.99"></a>
<FONT color="green">100</FONT>          clearWall(centerX, centerY, SOUTH);<a name="line.100"></a>
<FONT color="green">101</FONT>          clearWall(centerX, centerY, EAST);<a name="line.101"></a>
<FONT color="green">102</FONT>          clearWall(centerX + 1, centerY, SOUTH);<a name="line.102"></a>
<FONT color="green">103</FONT>          clearWall(centerX, centerY + 1, EAST);<a name="line.103"></a>
<FONT color="green">104</FONT>       }<a name="line.104"></a>
<FONT color="green">105</FONT>    <a name="line.105"></a>
<FONT color="green">106</FONT>       /**<a name="line.106"></a>
<FONT color="green">107</FONT>        * Clear all the walls of the maze and set the default corner wall.<a name="line.107"></a>
<FONT color="green">108</FONT>        */<a name="line.108"></a>
<FONT color="green">109</FONT>       public void clearMaze()<a name="line.109"></a>
<FONT color="green">110</FONT>       {<a name="line.110"></a>
<FONT color="green">111</FONT>          rwalls.clear();<a name="line.111"></a>
<FONT color="green">112</FONT>          cwalls.clear();<a name="line.112"></a>
<FONT color="green">113</FONT>          setWall(1, height, EAST);<a name="line.113"></a>
<FONT color="green">114</FONT>       }<a name="line.114"></a>
<FONT color="green">115</FONT>    <a name="line.115"></a>
<FONT color="green">116</FONT>       /**<a name="line.116"></a>
<FONT color="green">117</FONT>        * Clear/disable a wall segment.<a name="line.117"></a>
<FONT color="green">118</FONT>        * @param x<a name="line.118"></a>
<FONT color="green">119</FONT>        * @param y<a name="line.119"></a>
<FONT color="green">120</FONT>        * @param dir<a name="line.120"></a>
<FONT color="green">121</FONT>        */<a name="line.121"></a>
<FONT color="green">122</FONT>       public void clearWall(int x, int y, int dir)<a name="line.122"></a>
<FONT color="green">123</FONT>       {<a name="line.123"></a>
<FONT color="green">124</FONT>          //Check for the boundary conditions<a name="line.124"></a>
<FONT color="green">125</FONT>          if ( ( (dir == NORTH) &amp;&amp; (y == 1)) ||<a name="line.125"></a>
<FONT color="green">126</FONT>              ( (dir == EAST) &amp;&amp; (x == width)) ||<a name="line.126"></a>
<FONT color="green">127</FONT>              ( (dir == SOUTH) &amp;&amp; (y == height)) ||<a name="line.127"></a>
<FONT color="green">128</FONT>              ( (dir == WEST) &amp;&amp; (x == 1)))<a name="line.128"></a>
<FONT color="green">129</FONT>             return;<a name="line.129"></a>
<FONT color="green">130</FONT>    <a name="line.130"></a>
<FONT color="green">131</FONT>          if (x &gt; width || y &gt; height || x &lt; 1 || y &lt; 1)<a name="line.131"></a>
<FONT color="green">132</FONT>             return;<a name="line.132"></a>
<FONT color="green">133</FONT>          x--;<a name="line.133"></a>
<FONT color="green">134</FONT>          y--;<a name="line.134"></a>
<FONT color="green">135</FONT>    <a name="line.135"></a>
<FONT color="green">136</FONT>          if (dir == NORTH)<a name="line.136"></a>
<FONT color="green">137</FONT>             y--;<a name="line.137"></a>
<FONT color="green">138</FONT>          if (dir == WEST)<a name="line.138"></a>
<FONT color="green">139</FONT>             x--;<a name="line.139"></a>
<FONT color="green">140</FONT>    <a name="line.140"></a>
<FONT color="green">141</FONT>          if (dir == NORTH || dir == SOUTH)<a name="line.141"></a>
<FONT color="green">142</FONT>          {<a name="line.142"></a>
<FONT color="green">143</FONT>             if (rwalls.get(y * width + x))<a name="line.143"></a>
<FONT color="green">144</FONT>             {<a name="line.144"></a>
<FONT color="green">145</FONT>                rwalls.clear(y * width + x);<a name="line.145"></a>
<FONT color="green">146</FONT>                super.notifyListeners(new MazeCell(x + 1, y + 1));<a name="line.146"></a>
<FONT color="green">147</FONT>             }<a name="line.147"></a>
<FONT color="green">148</FONT>          }<a name="line.148"></a>
<FONT color="green">149</FONT>          else<a name="line.149"></a>
<FONT color="green">150</FONT>          {<a name="line.150"></a>
<FONT color="green">151</FONT>             if (cwalls.get(x * height + y))<a name="line.151"></a>
<FONT color="green">152</FONT>             {<a name="line.152"></a>
<FONT color="green">153</FONT>                cwalls.clear(x * height + y);<a name="line.153"></a>
<FONT color="green">154</FONT>                super.notifyListeners(new MazeCell(x + 1, y + 1));<a name="line.154"></a>
<FONT color="green">155</FONT>             }<a name="line.155"></a>
<FONT color="green">156</FONT>          }<a name="line.156"></a>
<FONT color="green">157</FONT>       }<a name="line.157"></a>
<FONT color="green">158</FONT>    <a name="line.158"></a>
<FONT color="green">159</FONT>       /**<a name="line.159"></a>
<FONT color="green">160</FONT>        * Make a deep copy of this maze model.<a name="line.160"></a>
<FONT color="green">161</FONT>        */<a name="line.161"></a>
<FONT color="green">162</FONT>       @Override<a name="line.162"></a>
<FONT color="green">163</FONT>       public MazeModel clone()<a name="line.163"></a>
<FONT color="green">164</FONT>       {<a name="line.164"></a>
<FONT color="green">165</FONT>          try<a name="line.165"></a>
<FONT color="green">166</FONT>          {<a name="line.166"></a>
<FONT color="green">167</FONT>             MazeModel mm = (MazeModel) super.clone();<a name="line.167"></a>
<FONT color="green">168</FONT>             mm.rwalls = (BitSet) rwalls.clone();<a name="line.168"></a>
<FONT color="green">169</FONT>             mm.cwalls = (BitSet) cwalls.clone();<a name="line.169"></a>
<FONT color="green">170</FONT>             return mm;<a name="line.170"></a>
<FONT color="green">171</FONT>          }<a name="line.171"></a>
<FONT color="green">172</FONT>          catch (CloneNotSupportedException e)<a name="line.172"></a>
<FONT color="green">173</FONT>          {<a name="line.173"></a>
<FONT color="green">174</FONT>             throw new RuntimeException(e);<a name="line.174"></a>
<FONT color="green">175</FONT>          }<a name="line.175"></a>
<FONT color="green">176</FONT>       }<a name="line.176"></a>
<FONT color="green">177</FONT>    <a name="line.177"></a>
<FONT color="green">178</FONT>       /**<a name="line.178"></a>
<FONT color="green">179</FONT>        * Randomizes all the walls of this maze.<a name="line.179"></a>
<FONT color="green">180</FONT>        */<a name="line.180"></a>
<FONT color="green">181</FONT>       public void generateRandomMaze()<a name="line.181"></a>
<FONT color="green">182</FONT>       {<a name="line.182"></a>
<FONT color="green">183</FONT>          this.setAllWalls();<a name="line.183"></a>
<FONT color="green">184</FONT>    <a name="line.184"></a>
<FONT color="green">185</FONT>          final Random rand = new Random();<a name="line.185"></a>
<FONT color="green">186</FONT>          for (int x = 1; x &lt;= this.getSize().width; x++)<a name="line.186"></a>
<FONT color="green">187</FONT>          {<a name="line.187"></a>
<FONT color="green">188</FONT>             for (int y = 1; y &lt;= this.getSize().height; y++)<a name="line.188"></a>
<FONT color="green">189</FONT>             {<a name="line.189"></a>
<FONT color="green">190</FONT>                final MazeCell cell = new MazeCell(x, y);<a name="line.190"></a>
<FONT color="green">191</FONT>                this.getWall(cell, Direction.East).set(rand.nextBoolean());<a name="line.191"></a>
<FONT color="green">192</FONT>                this.getWall(cell, Direction.South).set(rand.nextBoolean());<a name="line.192"></a>
<FONT color="green">193</FONT>             }<a name="line.193"></a>
<FONT color="green">194</FONT>          }<a name="line.194"></a>
<FONT color="green">195</FONT>          setWall(1, height, EAST); // Set mandatory wall.<a name="line.195"></a>
<FONT color="green">196</FONT>          clearWall(1, height, NORTH); // Must be clear.<a name="line.196"></a>
<FONT color="green">197</FONT>          clearWall(1, height - 1, NORTH); // Clear just to give it a better chance.<a name="line.197"></a>
<FONT color="green">198</FONT>          clearWall(1, height - 2, NORTH); // Clear just to give it a better chance.<a name="line.198"></a>
<FONT color="green">199</FONT>          clearWall(1, height - 1, EAST); // Clear just to give it a better chance.<a name="line.199"></a>
<FONT color="green">200</FONT>          clearWall(2, height - 1, EAST); // Clear just to give it a better chance.<a name="line.200"></a>
<FONT color="green">201</FONT>    <a name="line.201"></a>
<FONT color="green">202</FONT>          this.clearCenterWalls();<a name="line.202"></a>
<FONT color="green">203</FONT>          // Open one wall into the center.<a name="line.203"></a>
<FONT color="green">204</FONT>          List&lt;MazeWall&gt; winningBorder = this.getWinningBorderWalls();<a name="line.204"></a>
<FONT color="green">205</FONT>          for (MazeWall wall : winningBorder)<a name="line.205"></a>
<FONT color="green">206</FONT>             wall.set(true);<a name="line.206"></a>
<FONT color="green">207</FONT>          winningBorder.get(rand.nextInt(winningBorder.size())).set(false);<a name="line.207"></a>
<FONT color="green">208</FONT>    <a name="line.208"></a>
<FONT color="green">209</FONT>       }<a name="line.209"></a>
<FONT color="green">210</FONT>    <a name="line.210"></a>
<FONT color="green">211</FONT>       /**<a name="line.211"></a>
<FONT color="green">212</FONT>        * Get the size or dimension of this maze in columns by rows.<a name="line.212"></a>
<FONT color="green">213</FONT>        * @return The current size of this maze model.<a name="line.213"></a>
<FONT color="green">214</FONT>        */<a name="line.214"></a>
<FONT color="green">215</FONT>       public Dimension getSize()<a name="line.215"></a>
<FONT color="green">216</FONT>       {<a name="line.216"></a>
<FONT color="green">217</FONT>          return new Dimension(width, height);<a name="line.217"></a>
<FONT color="green">218</FONT>       }<a name="line.218"></a>
<FONT color="green">219</FONT>    <a name="line.219"></a>
<FONT color="green">220</FONT>       /**<a name="line.220"></a>
<FONT color="green">221</FONT>        * Get the location of where the robot starts in the maze. Using this instead<a name="line.221"></a>
<FONT color="green">222</FONT>        * of the hard coded location allows it to be changed in the future.<a name="line.222"></a>
<FONT color="green">223</FONT>        * @return Starting cell location.<a name="line.223"></a>
<FONT color="green">224</FONT>        */<a name="line.224"></a>
<FONT color="green">225</FONT>       public MazeCell getStartingCell()<a name="line.225"></a>
<FONT color="green">226</FONT>       {<a name="line.226"></a>
<FONT color="green">227</FONT>          return new MazeCell(1, this.height);<a name="line.227"></a>
<FONT color="green">228</FONT>       }<a name="line.228"></a>
<FONT color="green">229</FONT>    <a name="line.229"></a>
<FONT color="green">230</FONT>       /**<a name="line.230"></a>
<FONT color="green">231</FONT>        * Is the wall set/enabled.<a name="line.231"></a>
<FONT color="green">232</FONT>        * @param x<a name="line.232"></a>
<FONT color="green">233</FONT>        * @param y<a name="line.233"></a>
<FONT color="green">234</FONT>        * @param dir Direction of the wall from the cell center.<a name="line.234"></a>
<FONT color="green">235</FONT>        * @return true if the wall is set.<a name="line.235"></a>
<FONT color="green">236</FONT>        */<a name="line.236"></a>
<FONT color="green">237</FONT>       public boolean getWall(int x, int y, int dir)<a name="line.237"></a>
<FONT color="green">238</FONT>       {<a name="line.238"></a>
<FONT color="green">239</FONT>          //Check for the boundary conditions<a name="line.239"></a>
<FONT color="green">240</FONT>          if ( ( (dir == NORTH) &amp;&amp; (y == 1)) ||<a name="line.240"></a>
<FONT color="green">241</FONT>              ( (dir == EAST) &amp;&amp; (x == width)) ||<a name="line.241"></a>
<FONT color="green">242</FONT>              ( (dir == SOUTH) &amp;&amp; (y == height)) ||<a name="line.242"></a>
<FONT color="green">243</FONT>              ( (dir == WEST) &amp;&amp; (x == 1)))<a name="line.243"></a>
<FONT color="green">244</FONT>             return true;<a name="line.244"></a>
<FONT color="green">245</FONT>    <a name="line.245"></a>
<FONT color="green">246</FONT>          if ( (x &gt; width) || (y &gt; height) || (x &lt; 1) || (y &lt; 1))<a name="line.246"></a>
<FONT color="green">247</FONT>             return true;<a name="line.247"></a>
<FONT color="green">248</FONT>          x--;<a name="line.248"></a>
<FONT color="green">249</FONT>          y--;<a name="line.249"></a>
<FONT color="green">250</FONT>    <a name="line.250"></a>
<FONT color="green">251</FONT>          if (dir == NORTH)<a name="line.251"></a>
<FONT color="green">252</FONT>             y--;<a name="line.252"></a>
<FONT color="green">253</FONT>          if (dir == WEST)<a name="line.253"></a>
<FONT color="green">254</FONT>             x--;<a name="line.254"></a>
<FONT color="green">255</FONT>    <a name="line.255"></a>
<FONT color="green">256</FONT>          if (dir == NORTH || dir == SOUTH)<a name="line.256"></a>
<FONT color="green">257</FONT>             return rwalls.get(y * width + x);<a name="line.257"></a>
<FONT color="green">258</FONT>          else<a name="line.258"></a>
<FONT color="green">259</FONT>             return cwalls.get(x * height + y);<a name="line.259"></a>
<FONT color="green">260</FONT>       }<a name="line.260"></a>
<FONT color="green">261</FONT>    <a name="line.261"></a>
<FONT color="green">262</FONT>       /**<a name="line.262"></a>
<FONT color="green">263</FONT>        * Get an object that can then be checked or changed.<a name="line.263"></a>
<FONT color="green">264</FONT>        * @param cell The cell containing the wall you want.<a name="line.264"></a>
<FONT color="green">265</FONT>        * @param direction The direction of the wall you want from within the given<a name="line.265"></a>
<FONT color="green">266</FONT>        *           cell.<a name="line.266"></a>
<FONT color="green">267</FONT>        * @return A &lt;code&gt;MazeWall&lt;/code&gt; of the specified location.<a name="line.267"></a>
<FONT color="green">268</FONT>        */<a name="line.268"></a>
<FONT color="green">269</FONT>       public MazeWall getWall(final MazeCell cell, final Direction direction)<a name="line.269"></a>
<FONT color="green">270</FONT>       {<a name="line.270"></a>
<FONT color="green">271</FONT>          return new MazeWall()<a name="line.271"></a>
<FONT color="green">272</FONT>          {<a name="line.272"></a>
<FONT color="green">273</FONT>             @Override<a name="line.273"></a>
<FONT color="green">274</FONT>             public boolean isSet()<a name="line.274"></a>
<FONT color="green">275</FONT>             {<a name="line.275"></a>
<FONT color="green">276</FONT>                return getWall(cell.getX(), cell.getY(), direction.getIndex());<a name="line.276"></a>
<FONT color="green">277</FONT>             }<a name="line.277"></a>
<FONT color="green">278</FONT>    <a name="line.278"></a>
<FONT color="green">279</FONT>             @Override<a name="line.279"></a>
<FONT color="green">280</FONT>             public void set(boolean value)<a name="line.280"></a>
<FONT color="green">281</FONT>             {<a name="line.281"></a>
<FONT color="green">282</FONT>                if (value)<a name="line.282"></a>
<FONT color="green">283</FONT>                   setWall(cell.getX(), cell.getY(), direction.getIndex());<a name="line.283"></a>
<FONT color="green">284</FONT>                else<a name="line.284"></a>
<FONT color="green">285</FONT>                   clearWall(cell.getX(), cell.getY(), direction.getIndex());<a name="line.285"></a>
<FONT color="green">286</FONT>             }<a name="line.286"></a>
<FONT color="green">287</FONT>          };<a name="line.287"></a>
<FONT color="green">288</FONT>       }<a name="line.288"></a>
<FONT color="green">289</FONT>    <a name="line.289"></a>
<FONT color="green">290</FONT>       /**<a name="line.290"></a>
<FONT color="green">291</FONT>        * Get the line of walls that surround the center.<a name="line.291"></a>
<FONT color="green">292</FONT>        * @return A list of walls.<a name="line.292"></a>
<FONT color="green">293</FONT>        */<a name="line.293"></a>
<FONT color="green">294</FONT>       private List&lt;MazeWall&gt; getWinningBorderWalls()<a name="line.294"></a>
<FONT color="green">295</FONT>       {<a name="line.295"></a>
<FONT color="green">296</FONT>          final List&lt;MazeWall&gt; centerWalls = new ArrayList&lt;MazeWall&gt;();<a name="line.296"></a>
<FONT color="green">297</FONT>    <a name="line.297"></a>
<FONT color="green">298</FONT>          MazeCell[] winningCells = this.getWinningCells();<a name="line.298"></a>
<FONT color="green">299</FONT>          if (winningCells.length != 4)<a name="line.299"></a>
<FONT color="green">300</FONT>             throw new RuntimeException("This was written for winning cell groups of 4 only");<a name="line.300"></a>
<FONT color="green">301</FONT>          centerWalls.add(this.getWall(winningCells[0], Direction.West));<a name="line.301"></a>
<FONT color="green">302</FONT>          centerWalls.add(this.getWall(winningCells[0], Direction.North));<a name="line.302"></a>
<FONT color="green">303</FONT>          centerWalls.add(this.getWall(winningCells[1], Direction.North));<a name="line.303"></a>
<FONT color="green">304</FONT>          centerWalls.add(this.getWall(winningCells[1], Direction.East));<a name="line.304"></a>
<FONT color="green">305</FONT>          centerWalls.add(this.getWall(winningCells[2], Direction.West));<a name="line.305"></a>
<FONT color="green">306</FONT>          centerWalls.add(this.getWall(winningCells[2], Direction.South));<a name="line.306"></a>
<FONT color="green">307</FONT>          centerWalls.add(this.getWall(winningCells[3], Direction.South));<a name="line.307"></a>
<FONT color="green">308</FONT>          centerWalls.add(this.getWall(winningCells[3], Direction.East));<a name="line.308"></a>
<FONT color="green">309</FONT>    <a name="line.309"></a>
<FONT color="green">310</FONT>          return centerWalls;<a name="line.310"></a>
<FONT color="green">311</FONT>       }<a name="line.311"></a>
<FONT color="green">312</FONT>    <a name="line.312"></a>
<FONT color="green">313</FONT>       /**<a name="line.313"></a>
<FONT color="green">314</FONT>        * Gets the maze cells that make up the winning center of the maze. This<a name="line.314"></a>
<FONT color="green">315</FONT>        * method should be used to allow the location of the winning cells to be<a name="line.315"></a>
<FONT color="green">316</FONT>        * changed later.<a name="line.316"></a>
<FONT color="green">317</FONT>        * @return An array of the winning cell locations in order.<a name="line.317"></a>
<FONT color="green">318</FONT>        */<a name="line.318"></a>
<FONT color="green">319</FONT>       public MazeCell[] getWinningCells()<a name="line.319"></a>
<FONT color="green">320</FONT>       {<a name="line.320"></a>
<FONT color="green">321</FONT>          final int centerY = height / 2;<a name="line.321"></a>
<FONT color="green">322</FONT>          final int centerX = width / 2;<a name="line.322"></a>
<FONT color="green">323</FONT>          MazeCell[] result = new MazeCell[]<a name="line.323"></a>
<FONT color="green">324</FONT>          {<a name="line.324"></a>
<FONT color="green">325</FONT>             new MazeCell(centerX, centerY), new MazeCell(centerX + 1, centerY),<a name="line.325"></a>
<FONT color="green">326</FONT>             new MazeCell(centerX, centerY + 1), new MazeCell(centerX + 1, centerY + 1)<a name="line.326"></a>
<FONT color="green">327</FONT>          };<a name="line.327"></a>
<FONT color="green">328</FONT>          Arrays.sort(result);<a name="line.328"></a>
<FONT color="green">329</FONT>          return result;<a name="line.329"></a>
<FONT color="green">330</FONT>       }<a name="line.330"></a>
<FONT color="green">331</FONT>    <a name="line.331"></a>
<FONT color="green">332</FONT>       /**<a name="line.332"></a>
<FONT color="green">333</FONT>        * This function is basically isLegal with the added capability of returning<a name="line.333"></a>
<FONT color="green">334</FONT>        * the peg locations that are bad.&lt;br /&gt;<a name="line.334"></a>
<FONT color="green">335</FONT>        * There are rules that must be upheld to be a valid maze.&lt;br /&gt;<a name="line.335"></a>
<FONT color="green">336</FONT>        * Rule 1: There is a wall next to the starting square.&lt;br /&gt;<a name="line.336"></a>
<FONT color="green">337</FONT>        * Rule 2: There is one and only one way into the center of the maze.&lt;br /&gt;<a name="line.337"></a>
<FONT color="green">338</FONT>        * Even though I've coded this to accept a variable size in the future I<a name="line.338"></a>
<FONT color="green">339</FONT>        * shall still assume here that the total size will always be even.<a name="line.339"></a>
<FONT color="green">340</FONT>        * @return A &lt;code&gt;set&lt;/code&gt; of points where each point represents an<a name="line.340"></a>
<FONT color="green">341</FONT>        *         illegal peg.<a name="line.341"></a>
<FONT color="green">342</FONT>        */<a name="line.342"></a>
<FONT color="green">343</FONT>       public Set&lt;MazeCellPeg&gt; illegalPegs()<a name="line.343"></a>
<FONT color="green">344</FONT>       {<a name="line.344"></a>
<FONT color="green">345</FONT>          TreeSet&lt;MazeCellPeg&gt; badPoints = new TreeSet&lt;MazeCellPeg&gt;();<a name="line.345"></a>
<FONT color="green">346</FONT>    <a name="line.346"></a>
<FONT color="green">347</FONT>          int column = width / 2;<a name="line.347"></a>
<FONT color="green">348</FONT>          int row = height / 2;<a name="line.348"></a>
<FONT color="green">349</FONT>    <a name="line.349"></a>
<FONT color="green">350</FONT>          if (!isCenterOpen())<a name="line.350"></a>
<FONT color="green">351</FONT>          {<a name="line.351"></a>
<FONT color="green">352</FONT>             badPoints.add(new MazeCellPeg(column - 1, row - 1));<a name="line.352"></a>
<FONT color="green">353</FONT>             badPoints.add(new MazeCellPeg(column - 1, row));<a name="line.353"></a>
<FONT color="green">354</FONT>             badPoints.add(new MazeCellPeg(column - 1, row + 1));<a name="line.354"></a>
<FONT color="green">355</FONT>             badPoints.add(new MazeCellPeg(column, row - 1));<a name="line.355"></a>
<FONT color="green">356</FONT>             badPoints.add(new MazeCellPeg(column, row + 1));<a name="line.356"></a>
<FONT color="green">357</FONT>             badPoints.add(new MazeCellPeg(column + 1, row - 1));<a name="line.357"></a>
<FONT color="green">358</FONT>             badPoints.add(new MazeCellPeg(column + 1, row));<a name="line.358"></a>
<FONT color="green">359</FONT>             badPoints.add(new MazeCellPeg(column + 1, row + 1));<a name="line.359"></a>
<FONT color="green">360</FONT>          } //All of the center pegs are connected<a name="line.360"></a>
<FONT color="green">361</FONT>    <a name="line.361"></a>
<FONT color="green">362</FONT>          //Offshoot of Rule 2 is that the center of the maze is an open peg<a name="line.362"></a>
<FONT color="green">363</FONT>          if (!isCenterLegal())<a name="line.363"></a>
<FONT color="green">364</FONT>             badPoints.add(new MazeCellPeg(column, row));<a name="line.364"></a>
<FONT color="green">365</FONT>    <a name="line.365"></a>
<FONT color="green">366</FONT>          //Rule 3: There must be at least one wall coming from every peg<a name="line.366"></a>
<FONT color="green">367</FONT>          //Except for the lone center peg<a name="line.367"></a>
<FONT color="green">368</FONT>          for (int i = 1; i &lt;= width; i++)<a name="line.368"></a>
<FONT color="green">369</FONT>          {<a name="line.369"></a>
<FONT color="green">370</FONT>             for (int j = 1; j &lt;= height; j++)<a name="line.370"></a>
<FONT color="green">371</FONT>             {<a name="line.371"></a>
<FONT color="green">372</FONT>                if (!isPegLegal(i, j))<a name="line.372"></a>
<FONT color="green">373</FONT>                   badPoints.add(new MazeCellPeg(i, j));<a name="line.373"></a>
<FONT color="green">374</FONT>             }<a name="line.374"></a>
<FONT color="green">375</FONT>          }<a name="line.375"></a>
<FONT color="green">376</FONT>    <a name="line.376"></a>
<FONT color="green">377</FONT>          return badPoints;<a name="line.377"></a>
<FONT color="green">378</FONT>       }<a name="line.378"></a>
<FONT color="green">379</FONT>    <a name="line.379"></a>
<FONT color="green">380</FONT>       /**<a name="line.380"></a>
<FONT color="green">381</FONT>        * Is the peg in the center of the maze legal.<a name="line.381"></a>
<FONT color="green">382</FONT>        * @return true if the center peg does not have any walls touching it.<a name="line.382"></a>
<FONT color="green">383</FONT>        */<a name="line.383"></a>
<FONT color="green">384</FONT>       public boolean isCenterLegal()<a name="line.384"></a>
<FONT color="green">385</FONT>       {<a name="line.385"></a>
<FONT color="green">386</FONT>          int row = height / 2;<a name="line.386"></a>
<FONT color="green">387</FONT>          int column = width / 2;<a name="line.387"></a>
<FONT color="green">388</FONT>          if (getWall(column, row, SOUTH) ||<a name="line.388"></a>
<FONT color="green">389</FONT>              getWall(column, row, EAST) ||<a name="line.389"></a>
<FONT color="green">390</FONT>              getWall(column + 1, row, SOUTH) ||<a name="line.390"></a>
<FONT color="green">391</FONT>              getWall(column, row + 1, EAST))<a name="line.391"></a>
<FONT color="green">392</FONT>             return false;<a name="line.392"></a>
<FONT color="green">393</FONT>          return true;<a name="line.393"></a>
<FONT color="green">394</FONT>       }<a name="line.394"></a>
<FONT color="green">395</FONT>    <a name="line.395"></a>
<FONT color="green">396</FONT>       /**<a name="line.396"></a>
<FONT color="green">397</FONT>        * Is there a way in to the maze center.<a name="line.397"></a>
<FONT color="green">398</FONT>        * @return true if the center of the maze has one and only one way in.<a name="line.398"></a>
<FONT color="green">399</FONT>        */<a name="line.399"></a>
<FONT color="green">400</FONT>       public boolean isCenterOpen()<a name="line.400"></a>
<FONT color="green">401</FONT>       {<a name="line.401"></a>
<FONT color="green">402</FONT>          int walls = 0;<a name="line.402"></a>
<FONT color="green">403</FONT>          for (MazeWall wall : this.getWinningBorderWalls())<a name="line.403"></a>
<FONT color="green">404</FONT>          {<a name="line.404"></a>
<FONT color="green">405</FONT>             if (wall.isSet())<a name="line.405"></a>
<FONT color="green">406</FONT>                walls++;<a name="line.406"></a>
<FONT color="green">407</FONT>          }<a name="line.407"></a>
<FONT color="green">408</FONT>          return walls == 7; // Only 7 out of 8 walls set.<a name="line.408"></a>
<FONT color="green">409</FONT>       }<a name="line.409"></a>
<FONT color="green">410</FONT>    <a name="line.410"></a>
<FONT color="green">411</FONT>       /**<a name="line.411"></a>
<FONT color="green">412</FONT>        * Is this a legal maze. Does not check if there is a clear path from the<a name="line.412"></a>
<FONT color="green">413</FONT>        * start to the center.<a name="line.413"></a>
<FONT color="green">414</FONT>        * @return true if all the pegs in the maze are legal.<a name="line.414"></a>
<FONT color="green">415</FONT>        */<a name="line.415"></a>
<FONT color="green">416</FONT>       public boolean isLegal()<a name="line.416"></a>
<FONT color="green">417</FONT>       {<a name="line.417"></a>
<FONT color="green">418</FONT>          //There are three rules that must be upheld to be a valid maze<a name="line.418"></a>
<FONT color="green">419</FONT>          //Rule 1: There is a wall next to the starting square<a name="line.419"></a>
<FONT color="green">420</FONT>          if (!getWall(1, height, EAST) || getWall(1, height, NORTH))<a name="line.420"></a>
<FONT color="green">421</FONT>             return false;<a name="line.421"></a>
<FONT color="green">422</FONT>          //Rule 2: There is one and only one way into the center of the maze<a name="line.422"></a>
<FONT color="green">423</FONT>          //Even though I've coded this to accept a variable size in the future<a name="line.423"></a>
<FONT color="green">424</FONT>          //I shall still assume here that the total size will always be even      <a name="line.424"></a>
<FONT color="green">425</FONT>          int row = height / 2, column = width / 2;<a name="line.425"></a>
<FONT color="green">426</FONT>          if (!isCenterLegal())<a name="line.426"></a>
<FONT color="green">427</FONT>             return false;<a name="line.427"></a>
<FONT color="green">428</FONT>    <a name="line.428"></a>
<FONT color="green">429</FONT>          //Offshoot of Rule 2 is that the center of the maze is an open peg<a name="line.429"></a>
<FONT color="green">430</FONT>          if (!isCenterOpen())<a name="line.430"></a>
<FONT color="green">431</FONT>             return false;<a name="line.431"></a>
<FONT color="green">432</FONT>    <a name="line.432"></a>
<FONT color="green">433</FONT>          //Rule 3: There must be at least one wall coming from every peg<a name="line.433"></a>
<FONT color="green">434</FONT>          //Except for the lone center peg<a name="line.434"></a>
<FONT color="green">435</FONT>          for (int i = 1; i &lt;= width; i++)<a name="line.435"></a>
<FONT color="green">436</FONT>          {<a name="line.436"></a>
<FONT color="green">437</FONT>             for (int j = 1; j &lt;= height; j++)<a name="line.437"></a>
<FONT color="green">438</FONT>             {<a name="line.438"></a>
<FONT color="green">439</FONT>                if ( (i == row &amp;&amp; j == column) || isPegLegal(i, j))<a name="line.439"></a>
<FONT color="green">440</FONT>                   continue;<a name="line.440"></a>
<FONT color="green">441</FONT>                return false;<a name="line.441"></a>
<FONT color="green">442</FONT>             }<a name="line.442"></a>
<FONT color="green">443</FONT>          }<a name="line.443"></a>
<FONT color="green">444</FONT>          return true;<a name="line.444"></a>
<FONT color="green">445</FONT>       }<a name="line.445"></a>
<FONT color="green">446</FONT>    <a name="line.446"></a>
<FONT color="green">447</FONT>       /**<a name="line.447"></a>
<FONT color="green">448</FONT>        * The peg is legal if at least one wall is attached to it. The North-West<a name="line.448"></a>
<FONT color="green">449</FONT>        * peg of the given Maze Cell is checked.<a name="line.449"></a>
<FONT color="green">450</FONT>        * @param x The Cell X coordinate.<a name="line.450"></a>
<FONT color="green">451</FONT>        * @param y The Cell Y coordinate.<a name="line.451"></a>
<FONT color="green">452</FONT>        * @return true if the peg has at least one wall touching it.<a name="line.452"></a>
<FONT color="green">453</FONT>        */<a name="line.453"></a>
<FONT color="green">454</FONT>       public boolean isPegLegal(int x, int y)<a name="line.454"></a>
<FONT color="green">455</FONT>       {<a name="line.455"></a>
<FONT color="green">456</FONT>          //This function is designed to give a lower-level view to the isLegal<a name="line.456"></a>
<FONT color="green">457</FONT>          //method by telling about a specific peg<a name="line.457"></a>
<FONT color="green">458</FONT>    <a name="line.458"></a>
<FONT color="green">459</FONT>          //The peg location is based off of the cell that it is in the NORTHWEST<a name="line.459"></a>
<FONT color="green">460</FONT>          //corner of.  Peg (1,1) is the only peg touching cell (1,1)<a name="line.460"></a>
<FONT color="green">461</FONT>          if (x &lt; 1 || y &lt; 1 || x &gt;= width || y &gt;= height)<a name="line.461"></a>
<FONT color="green">462</FONT>             return true;<a name="line.462"></a>
<FONT color="green">463</FONT>          //Every peg should have at least one wall attached to it<a name="line.463"></a>
<FONT color="green">464</FONT>          if (getWall(x, y, SOUTH) ||<a name="line.464"></a>
<FONT color="green">465</FONT>              getWall(x, y, EAST) ||<a name="line.465"></a>
<FONT color="green">466</FONT>              getWall(x + 1, y + 1, NORTH) ||<a name="line.466"></a>
<FONT color="green">467</FONT>              getWall(x + 1, y + 1, WEST))<a name="line.467"></a>
<FONT color="green">468</FONT>          {<a name="line.468"></a>
<FONT color="green">469</FONT>             //There are only three cases with walls that must be checked<a name="line.469"></a>
<FONT color="green">470</FONT>             //First is the starting square<a name="line.470"></a>
<FONT color="green">471</FONT>             if ( (x == 1) &amp;&amp; (y == height - 1))<a name="line.471"></a>
<FONT color="green">472</FONT>             {<a name="line.472"></a>
<FONT color="green">473</FONT>                if (getWall(1, height, EAST) &amp;&amp; !getWall(1, height, NORTH))<a name="line.473"></a>
<FONT color="green">474</FONT>                   return true;<a name="line.474"></a>
<FONT color="green">475</FONT>                else<a name="line.475"></a>
<FONT color="green">476</FONT>                   return false;<a name="line.476"></a>
<FONT color="green">477</FONT>             }<a name="line.477"></a>
<FONT color="green">478</FONT>    <a name="line.478"></a>
<FONT color="green">479</FONT>             //Second is that it is not the center peg<a name="line.479"></a>
<FONT color="green">480</FONT>             else if (x == (width / 2) &amp;&amp; y == (height / 2))<a name="line.480"></a>
<FONT color="green">481</FONT>                return isCenterLegal();<a name="line.481"></a>
<FONT color="green">482</FONT>    <a name="line.482"></a>
<FONT color="green">483</FONT>             //Third is the pegs surrounding the center square<a name="line.483"></a>
<FONT color="green">484</FONT>             else if ( (x &lt;= width / 2 &amp;&amp; y &lt;= height / 2) &amp;&amp;<a name="line.484"></a>
<FONT color="green">485</FONT>                      (x &gt;= width / 2 - 1 &amp;&amp; y &gt;= height / 2 - 1))<a name="line.485"></a>
<FONT color="green">486</FONT>                return isCenterOpen();<a name="line.486"></a>
<FONT color="green">487</FONT>             //There are no more reasons to check the walls<a name="line.487"></a>
<FONT color="green">488</FONT>             else<a name="line.488"></a>
<FONT color="green">489</FONT>                return true;<a name="line.489"></a>
<FONT color="green">490</FONT>          }<a name="line.490"></a>
<FONT color="green">491</FONT>          else<a name="line.491"></a>
<FONT color="green">492</FONT>          {<a name="line.492"></a>
<FONT color="green">493</FONT>             //The only exception to no wall is the center peg<a name="line.493"></a>
<FONT color="green">494</FONT>             if (x == width / 2 &amp;&amp; y == height / 2)<a name="line.494"></a>
<FONT color="green">495</FONT>                return true;<a name="line.495"></a>
<FONT color="green">496</FONT>             else<a name="line.496"></a>
<FONT color="green">497</FONT>                return false;<a name="line.497"></a>
<FONT color="green">498</FONT>          }<a name="line.498"></a>
<FONT color="green">499</FONT>       }<a name="line.499"></a>
<FONT color="green">500</FONT>    <a name="line.500"></a>
<FONT color="green">501</FONT>       public String loadMaze(InputStream in, boolean extended) throws IOException<a name="line.501"></a>
<FONT color="green">502</FONT>       {<a name="line.502"></a>
<FONT color="green">503</FONT>          if (extended)<a name="line.503"></a>
<FONT color="green">504</FONT>          {<a name="line.504"></a>
<FONT color="green">505</FONT>             DataInputStream dis = new DataInputStream(in);<a name="line.505"></a>
<FONT color="green">506</FONT>             String name = dis.readUTF();<a name="line.506"></a>
<FONT color="green">507</FONT>             setSize(new Dimension(dis.readInt(), dis.readInt()));<a name="line.507"></a>
<FONT color="green">508</FONT>    <a name="line.508"></a>
<FONT color="green">509</FONT>             int rwallSize = rwalls.size(), cwallSize = cwalls.size();<a name="line.509"></a>
<FONT color="green">510</FONT>             for (int i = 0; i &lt; rwallSize;)<a name="line.510"></a>
<FONT color="green">511</FONT>             {<a name="line.511"></a>
<FONT color="green">512</FONT>                byte bits = dis.readByte();<a name="line.512"></a>
<FONT color="green">513</FONT>                for (int j = 0; j &lt; 8 &amp;&amp; i &lt; rwallSize; j++, i++)<a name="line.513"></a>
<FONT color="green">514</FONT>                {<a name="line.514"></a>
<FONT color="green">515</FONT>                   rwalls.set(i, (bits &amp; 1) == 1);<a name="line.515"></a>
<FONT color="green">516</FONT>                   bits &gt;&gt;= 1;<a name="line.516"></a>
<FONT color="green">517</FONT>                }<a name="line.517"></a>
<FONT color="green">518</FONT>             }<a name="line.518"></a>
<FONT color="green">519</FONT>             for (int i = 0; i &lt; cwallSize;)<a name="line.519"></a>
<FONT color="green">520</FONT>             {<a name="line.520"></a>
<FONT color="green">521</FONT>                byte bits = dis.readByte();<a name="line.521"></a>
<FONT color="green">522</FONT>                for (int j = 0; j &lt; 8 &amp;&amp; i &lt; cwallSize; j++, i++)<a name="line.522"></a>
<FONT color="green">523</FONT>                {<a name="line.523"></a>
<FONT color="green">524</FONT>                   cwalls.set(i, (bits &amp; 1) == 1);<a name="line.524"></a>
<FONT color="green">525</FONT>                   bits &gt;&gt;= 1;<a name="line.525"></a>
<FONT color="green">526</FONT>                }<a name="line.526"></a>
<FONT color="green">527</FONT>             }<a name="line.527"></a>
<FONT color="green">528</FONT>             return name;<a name="line.528"></a>
<FONT color="green">529</FONT>          }<a name="line.529"></a>
<FONT color="green">530</FONT>          else<a name="line.530"></a>
<FONT color="green">531</FONT>          {<a name="line.531"></a>
<FONT color="green">532</FONT>             //This is the formatting of the .MAZ files found online<a name="line.532"></a>
<FONT color="green">533</FONT>             //This format is 4 times more inefficient than needs be<a name="line.533"></a>
<FONT color="green">534</FONT>             //but it is a format that is already present<a name="line.534"></a>
<FONT color="green">535</FONT>             byte[] fileContents = new byte[256];<a name="line.535"></a>
<FONT color="green">536</FONT>             setSize(new Dimension(DEFAULT_SIZE, DEFAULT_SIZE));<a name="line.536"></a>
<FONT color="green">537</FONT>    <a name="line.537"></a>
<FONT color="green">538</FONT>             if (in.available() != 256)<a name="line.538"></a>
<FONT color="green">539</FONT>                throw new IOException("Invalid format");<a name="line.539"></a>
<FONT color="green">540</FONT>    <a name="line.540"></a>
<FONT color="green">541</FONT>             in.read(fileContents);<a name="line.541"></a>
<FONT color="green">542</FONT>    <a name="line.542"></a>
<FONT color="green">543</FONT>             for (int i = 1; i &lt;= 16; i++)<a name="line.543"></a>
<FONT color="green">544</FONT>             {<a name="line.544"></a>
<FONT color="green">545</FONT>                for (int j = 16; j &gt; 0; j--)<a name="line.545"></a>
<FONT color="green">546</FONT>                {<a name="line.546"></a>
<FONT color="green">547</FONT>                   byte cellWalls = fileContents[16 * (i - 1) + (16 - j)];<a name="line.547"></a>
<FONT color="green">548</FONT>                   if ( (cellWalls &amp; 1) == 1)<a name="line.548"></a>
<FONT color="green">549</FONT>                      this.setWall(i, j, NORTH);<a name="line.549"></a>
<FONT color="green">550</FONT>                   else<a name="line.550"></a>
<FONT color="green">551</FONT>                      this.clearWall(i, j, NORTH);<a name="line.551"></a>
<FONT color="green">552</FONT>    <a name="line.552"></a>
<FONT color="green">553</FONT>                   if ( (cellWalls &amp; 2) == 2)<a name="line.553"></a>
<FONT color="green">554</FONT>                      this.setWall(i, j, EAST);<a name="line.554"></a>
<FONT color="green">555</FONT>                   else<a name="line.555"></a>
<FONT color="green">556</FONT>                      this.clearWall(i, j, EAST);<a name="line.556"></a>
<FONT color="green">557</FONT>    <a name="line.557"></a>
<FONT color="green">558</FONT>                   if ( (cellWalls &amp; 4) == 4)<a name="line.558"></a>
<FONT color="green">559</FONT>                      this.setWall(i, j, SOUTH);<a name="line.559"></a>
<FONT color="green">560</FONT>                   else<a name="line.560"></a>
<FONT color="green">561</FONT>                      this.clearWall(i, j, SOUTH);<a name="line.561"></a>
<FONT color="green">562</FONT>    <a name="line.562"></a>
<FONT color="green">563</FONT>                   if ( (cellWalls &amp; 8) == 8)<a name="line.563"></a>
<FONT color="green">564</FONT>                      this.setWall(i, j, WEST);<a name="line.564"></a>
<FONT color="green">565</FONT>                   else<a name="line.565"></a>
<FONT color="green">566</FONT>                      this.clearWall(i, j, WEST);<a name="line.566"></a>
<FONT color="green">567</FONT>                } // for(int j=16; j&gt;0; j--)<a name="line.567"></a>
<FONT color="green">568</FONT>             } // for(int i=1; i&lt;=16; i++)<a name="line.568"></a>
<FONT color="green">569</FONT>             return null;<a name="line.569"></a>
<FONT color="green">570</FONT>          }<a name="line.570"></a>
<FONT color="green">571</FONT>       }<a name="line.571"></a>
<FONT color="green">572</FONT>    <a name="line.572"></a>
<FONT color="green">573</FONT>       public String loadMaze(String filename) throws FileNotFoundException, IOException<a name="line.573"></a>
<FONT color="green">574</FONT>       {<a name="line.574"></a>
<FONT color="green">575</FONT>          //Now for the actual file i/o<a name="line.575"></a>
<FONT color="green">576</FONT>          File file = new File(filename);<a name="line.576"></a>
<FONT color="green">577</FONT>          String name;<a name="line.577"></a>
<FONT color="green">578</FONT>          FileInputStream in = null;<a name="line.578"></a>
<FONT color="green">579</FONT>          in = new FileInputStream(file);<a name="line.579"></a>
<FONT color="green">580</FONT>          if (filename.toLowerCase().endsWith("maz"))<a name="line.580"></a>
<FONT color="green">581</FONT>             name = loadMaze(in, false); // Simple format.<a name="line.581"></a>
<FONT color="green">582</FONT>          else<a name="line.582"></a>
<FONT color="green">583</FONT>             name = loadMaze(in, true); // v2 format.<a name="line.583"></a>
<FONT color="green">584</FONT>          in.close();<a name="line.584"></a>
<FONT color="green">585</FONT>    <a name="line.585"></a>
<FONT color="green">586</FONT>          return name;<a name="line.586"></a>
<FONT color="green">587</FONT>       }<a name="line.587"></a>
<FONT color="green">588</FONT>    <a name="line.588"></a>
<FONT color="green">589</FONT>       public void saveMaze(String filename, String name) throws IOException<a name="line.589"></a>
<FONT color="green">590</FONT>       {<a name="line.590"></a>
<FONT color="green">591</FONT>          //This is the formatting of the .MAZ files found online<a name="line.591"></a>
<FONT color="green">592</FONT>          //This format is 4 times more inefficient than needs be<a name="line.592"></a>
<FONT color="green">593</FONT>          //but it is a format that is already present<a name="line.593"></a>
<FONT color="green">594</FONT>          if (name == null)<a name="line.594"></a>
<FONT color="green">595</FONT>          {<a name="line.595"></a>
<FONT color="green">596</FONT>             byte[] fileContents = new byte[256];<a name="line.596"></a>
<FONT color="green">597</FONT>             for (int i = 1; i &lt;= 16; i++)<a name="line.597"></a>
<FONT color="green">598</FONT>             {<a name="line.598"></a>
<FONT color="green">599</FONT>                for (int j = 16; j &gt; 0; j--)<a name="line.599"></a>
<FONT color="green">600</FONT>                {<a name="line.600"></a>
<FONT color="green">601</FONT>                   MazeCell cell = new MazeCell(i, j);<a name="line.601"></a>
<FONT color="green">602</FONT>                   byte cellWalls = 0;<a name="line.602"></a>
<FONT color="green">603</FONT>                   if (this.getWall(cell, Direction.North).isSet())<a name="line.603"></a>
<FONT color="green">604</FONT>                   {<a name="line.604"></a>
<FONT color="green">605</FONT>                      cellWalls = 1;<a name="line.605"></a>
<FONT color="green">606</FONT>                   }<a name="line.606"></a>
<FONT color="green">607</FONT>                   if (this.getWall(cell, Direction.East).isSet())<a name="line.607"></a>
<FONT color="green">608</FONT>                   {<a name="line.608"></a>
<FONT color="green">609</FONT>                      cellWalls += 2;<a name="line.609"></a>
<FONT color="green">610</FONT>                   }<a name="line.610"></a>
<FONT color="green">611</FONT>                   if (this.getWall(cell, Direction.South).isSet())<a name="line.611"></a>
<FONT color="green">612</FONT>                   {<a name="line.612"></a>
<FONT color="green">613</FONT>                      cellWalls += 4;<a name="line.613"></a>
<FONT color="green">614</FONT>                   }<a name="line.614"></a>
<FONT color="green">615</FONT>                   if (this.getWall(cell, Direction.West).isSet())<a name="line.615"></a>
<FONT color="green">616</FONT>                   {<a name="line.616"></a>
<FONT color="green">617</FONT>                      cellWalls += 8;<a name="line.617"></a>
<FONT color="green">618</FONT>                   }<a name="line.618"></a>
<FONT color="green">619</FONT>    <a name="line.619"></a>
<FONT color="green">620</FONT>                   fileContents[16 * (i - 1) + (16 - j)] = cellWalls;<a name="line.620"></a>
<FONT color="green">621</FONT>                }<a name="line.621"></a>
<FONT color="green">622</FONT>             }<a name="line.622"></a>
<FONT color="green">623</FONT>    <a name="line.623"></a>
<FONT color="green">624</FONT>             //Now for the actual file i/o<a name="line.624"></a>
<FONT color="green">625</FONT>             if (filename.toLowerCase().endsWith(".maz") == false)<a name="line.625"></a>
<FONT color="green">626</FONT>                filename = filename + ".maz";<a name="line.626"></a>
<FONT color="green">627</FONT>    <a name="line.627"></a>
<FONT color="green">628</FONT>             FileOutputStream out = new FileOutputStream(filename);<a name="line.628"></a>
<FONT color="green">629</FONT>             out.write(fileContents);<a name="line.629"></a>
<FONT color="green">630</FONT>             out.close();<a name="line.630"></a>
<FONT color="green">631</FONT>          } // if (name == null)<a name="line.631"></a>
<FONT color="green">632</FONT>          else<a name="line.632"></a>
<FONT color="green">633</FONT>          {<a name="line.633"></a>
<FONT color="green">634</FONT>             if (filename.toLowerCase().endsWith(".mz2") == false)<a name="line.634"></a>
<FONT color="green">635</FONT>                filename = filename + ".mz2";<a name="line.635"></a>
<FONT color="green">636</FONT>    <a name="line.636"></a>
<FONT color="green">637</FONT>             FileOutputStream out = new FileOutputStream(filename);<a name="line.637"></a>
<FONT color="green">638</FONT>             DataOutputStream dis = new DataOutputStream(out);<a name="line.638"></a>
<FONT color="green">639</FONT>             dis.writeUTF(name);<a name="line.639"></a>
<FONT color="green">640</FONT>             dis.writeInt(width);<a name="line.640"></a>
<FONT color="green">641</FONT>             dis.writeInt(height);<a name="line.641"></a>
<FONT color="green">642</FONT>    <a name="line.642"></a>
<FONT color="green">643</FONT>             int rwallSize = rwalls.size(), cwallSize = cwalls.size();<a name="line.643"></a>
<FONT color="green">644</FONT>             int rwallArraySize = rwalls.size() / 8;<a name="line.644"></a>
<FONT color="green">645</FONT>             if (rwalls.size() % 8 &gt; 0)<a name="line.645"></a>
<FONT color="green">646</FONT>                rwallArraySize++;<a name="line.646"></a>
<FONT color="green">647</FONT>             int cwallArraySize = cwalls.size() / 8;<a name="line.647"></a>
<FONT color="green">648</FONT>             if (cwalls.size() % 8 &gt; 0)<a name="line.648"></a>
<FONT color="green">649</FONT>                cwallArraySize++;<a name="line.649"></a>
<FONT color="green">650</FONT>             byte[] rwallArray = new byte[rwallArraySize];<a name="line.650"></a>
<FONT color="green">651</FONT>             byte[] cwallArray = new byte[cwallArraySize];<a name="line.651"></a>
<FONT color="green">652</FONT>             for (int i = 0; i &lt; rwallArray.length; i++)<a name="line.652"></a>
<FONT color="green">653</FONT>                rwallArray[i] = 0;<a name="line.653"></a>
<FONT color="green">654</FONT>             for (int i = 0; i &lt; cwallArray.length; i++)<a name="line.654"></a>
<FONT color="green">655</FONT>                cwallArray[i] = 0;<a name="line.655"></a>
<FONT color="green">656</FONT>    <a name="line.656"></a>
<FONT color="green">657</FONT>             int index = 0;<a name="line.657"></a>
<FONT color="green">658</FONT>    <a name="line.658"></a>
<FONT color="green">659</FONT>             for (int i = 0; i &lt; rwallSize; i++)<a name="line.659"></a>
<FONT color="green">660</FONT>             {<a name="line.660"></a>
<FONT color="green">661</FONT>                rwallArray[index] |= ( (rwalls.get(i) ? 1 : 0) &lt;&lt; (i % 8));<a name="line.661"></a>
<FONT color="green">662</FONT>                if ( (i + 1) % 8 == 0)<a name="line.662"></a>
<FONT color="green">663</FONT>                   index++;<a name="line.663"></a>
<FONT color="green">664</FONT>             }<a name="line.664"></a>
<FONT color="green">665</FONT>    <a name="line.665"></a>
<FONT color="green">666</FONT>             index = 0;<a name="line.666"></a>
<FONT color="green">667</FONT>    <a name="line.667"></a>
<FONT color="green">668</FONT>             for (int i = 0; i &lt; cwallSize; i++)<a name="line.668"></a>
<FONT color="green">669</FONT>             {<a name="line.669"></a>
<FONT color="green">670</FONT>                cwallArray[index] |= ( (cwalls.get(i) ? 1 : 0) &lt;&lt; (i % 8));<a name="line.670"></a>
<FONT color="green">671</FONT>                if ( (i + 1) % 8 == 0)<a name="line.671"></a>
<FONT color="green">672</FONT>                   index++;<a name="line.672"></a>
<FONT color="green">673</FONT>             }<a name="line.673"></a>
<FONT color="green">674</FONT>    <a name="line.674"></a>
<FONT color="green">675</FONT>             dis.write(rwallArray);<a name="line.675"></a>
<FONT color="green">676</FONT>             dis.write(cwallArray);<a name="line.676"></a>
<FONT color="green">677</FONT>             dis.close();<a name="line.677"></a>
<FONT color="green">678</FONT>          }<a name="line.678"></a>
<FONT color="green">679</FONT>    <a name="line.679"></a>
<FONT color="green">680</FONT>       }<a name="line.680"></a>
<FONT color="green">681</FONT>    <a name="line.681"></a>
<FONT color="green">682</FONT>       /**<a name="line.682"></a>
<FONT color="green">683</FONT>        * Set/Enable every wall in the maze.<a name="line.683"></a>
<FONT color="green">684</FONT>        */<a name="line.684"></a>
<FONT color="green">685</FONT>       public void setAllWalls()<a name="line.685"></a>
<FONT color="green">686</FONT>       {<a name="line.686"></a>
<FONT color="green">687</FONT>          this.rwalls.set(0, this.rwalls.size());<a name="line.687"></a>
<FONT color="green">688</FONT>          this.cwalls.set(0, this.cwalls.size());<a name="line.688"></a>
<FONT color="green">689</FONT>       }<a name="line.689"></a>
<FONT color="green">690</FONT>    <a name="line.690"></a>
<FONT color="green">691</FONT>       /**<a name="line.691"></a>
<FONT color="green">692</FONT>        * Set the size dimensions of this maze. The maze dimensions must always be<a name="line.692"></a>
<FONT color="green">693</FONT>        * even numbers.<a name="line.693"></a>
<FONT color="green">694</FONT>        * @param size The new number of rows and columns that make up the size of<a name="line.694"></a>
<FONT color="green">695</FONT>        *           this maze.<a name="line.695"></a>
<FONT color="green">696</FONT>        */<a name="line.696"></a>
<FONT color="green">697</FONT>       public void setSize(Dimension size)<a name="line.697"></a>
<FONT color="green">698</FONT>       {<a name="line.698"></a>
<FONT color="green">699</FONT>          width = size.width + size.width % 2;<a name="line.699"></a>
<FONT color="green">700</FONT>          height = size.height + size.height % 2;<a name="line.700"></a>
<FONT color="green">701</FONT>          rwalls = new BitSet(width * (height - 1));<a name="line.701"></a>
<FONT color="green">702</FONT>          cwalls = new BitSet( (width - 1) * height);<a name="line.702"></a>
<FONT color="green">703</FONT>       }<a name="line.703"></a>
<FONT color="green">704</FONT>    <a name="line.704"></a>
<FONT color="green">705</FONT>       public void setWall(int x, int y, int dir)<a name="line.705"></a>
<FONT color="green">706</FONT>       {<a name="line.706"></a>
<FONT color="green">707</FONT>          //Check for the boundary conditions<a name="line.707"></a>
<FONT color="green">708</FONT>          //First make sure that we're in the maze<a name="line.708"></a>
<FONT color="green">709</FONT>          if ( (x &lt; 1) || (y &lt; 1) || (x &gt; width) || (y &gt; height))<a name="line.709"></a>
<FONT color="green">710</FONT>             return;<a name="line.710"></a>
<FONT color="green">711</FONT>          //Second make sure that the wall isn't implied<a name="line.711"></a>
<FONT color="green">712</FONT>          if ( ( (dir == NORTH) &amp;&amp; (y == 1)) ||<a name="line.712"></a>
<FONT color="green">713</FONT>              ( (dir == EAST) &amp;&amp; (x == width)) ||<a name="line.713"></a>
<FONT color="green">714</FONT>              ( (dir == SOUTH) &amp;&amp; (y == height)) ||<a name="line.714"></a>
<FONT color="green">715</FONT>              ( (dir == WEST) &amp;&amp; (x == 1)))<a name="line.715"></a>
<FONT color="green">716</FONT>             return;<a name="line.716"></a>
<FONT color="green">717</FONT>    <a name="line.717"></a>
<FONT color="green">718</FONT>          x--;<a name="line.718"></a>
<FONT color="green">719</FONT>          y--;<a name="line.719"></a>
<FONT color="green">720</FONT>    <a name="line.720"></a>
<FONT color="green">721</FONT>          if (dir == NORTH)<a name="line.721"></a>
<FONT color="green">722</FONT>             y--;<a name="line.722"></a>
<FONT color="green">723</FONT>          if (dir == WEST)<a name="line.723"></a>
<FONT color="green">724</FONT>             x--;<a name="line.724"></a>
<FONT color="green">725</FONT>    <a name="line.725"></a>
<FONT color="green">726</FONT>          if (dir == NORTH || dir == SOUTH)<a name="line.726"></a>
<FONT color="green">727</FONT>          {<a name="line.727"></a>
<FONT color="green">728</FONT>             if (!rwalls.get(y * width + x))<a name="line.728"></a>
<FONT color="green">729</FONT>             {<a name="line.729"></a>
<FONT color="green">730</FONT>                rwalls.set(y * width + x);<a name="line.730"></a>
<FONT color="green">731</FONT>                super.notifyListeners(new MazeCell(x + 1, y + 1));<a name="line.731"></a>
<FONT color="green">732</FONT>             }<a name="line.732"></a>
<FONT color="green">733</FONT>          }<a name="line.733"></a>
<FONT color="green">734</FONT>          else<a name="line.734"></a>
<FONT color="green">735</FONT>          {<a name="line.735"></a>
<FONT color="green">736</FONT>             if (!cwalls.get(x * height + y))<a name="line.736"></a>
<FONT color="green">737</FONT>             {<a name="line.737"></a>
<FONT color="green">738</FONT>                cwalls.set(x * height + y);<a name="line.738"></a>
<FONT color="green">739</FONT>                super.notifyListeners(new MazeCell(x + 1, y + 1));<a name="line.739"></a>
<FONT color="green">740</FONT>             }<a name="line.740"></a>
<FONT color="green">741</FONT>          }<a name="line.741"></a>
<FONT color="green">742</FONT>    <a name="line.742"></a>
<FONT color="green">743</FONT>       }<a name="line.743"></a>
<FONT color="green">744</FONT>    }<a name="line.744"></a>




























































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